GF54.21-P-6070LE Front SAM Control Unit With Fuse and Relay Module, Component Description

GF54.21-P-6070LE Front SAM Control Unit With Fuse And Relay Module, Component Description

Component Identification:

Location
The front SAM control unit is located on the left of the engine compartment in the control unit box.

Task
The front SAM control unit has the following tasks:
^ Reading in of sensors, pickups and signals
^ Evaluation of input factors
^ Control of systems
^ Actuating components
^ Voltage supply to components
^ Switching consumers using relays

Reading in of sensors, pickups and signals
The input factors are read in with the following connections:
^ Direct line
^ AC bus (KB)
^ On-board electrical system LIN (LIN B7)
^ Interior CAN (CAN B)

Direct line
The signals from the following components are read via a direct line:
- Refrigerant pressure sensor (B12)
- Outside temperature indicator temperature sensor (B14)
- Hall sensor of steering column in/out motor (M20/1)
- Hall sensor of steering column up/down motor (M20/2)
- Left rear center air outlet potentiometer (R41/4r1)
- Right rear center air outlet potentiometer (R41/4r2)
- Right front brake pad contact sensor (S10/2)
- Brake fluid indicator switch (S11)
- Coolant level indicator switch (S41)
- Windshield washer system fluid level indicator switch (S42)

AC bus
The signals from the following components are read in via the AC bus:
- AAC multifunction sensor (B31/1)
- AAC [KLA] 4-way sun sensor (B32/2)

The refrigerant pressure sensor, AAC (KLA) multifunction sensor and the AAC [KLA] sun sensor (4 in total) signals are sent to the AAC (KLA) control unit (N22/1) over the AC bus.

On-board electrical system LIN
The signals for the following components are read in over the on-board electrical system LIN:
- Battery sensor (B95)

Interior CAN
The signals are read in by the front SAM control unit via the interior CAN.
The functions resulting therefrom are described in the corresponding function descriptions (see block diagram or function schematic).

Evaluation of input factors
The input factors are evaluated by the microprocessor and the corresponding components are actuated.

Control of systems
The front SAM control unit controls the following systems:
- Exterior lights [ABL]
- Wiper system (WSA)
- Electrically adjustable steering column (ESC [EVL])
- Fanfare horns
- Wiper rest heater

Actuation of components
Components are actuated with the following line:
^ Direct line

Direct line
The following components are actuated via a direct line:
- Left front lamp unit (E1)
- Right front lamp unit (E2)
- Model 221 as of 1.6.09 without code (498) Japan version:
- Left daytime running lights headlamp (E1/3)
- Right daytime running lights headlamp (E2/3)

- Model 216, model 221 up to 31.5.09, model 221 as of 1.6.09 without code (236) LED daytime running lights:
- Left front fog lamp (E5/1)
- Right front fog lamp (E5/2)

- For code (494) USA version:
- Left front side-marker lamp ((United States of America) E6/1)
- Right front side-marker lamp ((United States of America) E6/2)
- Stowage compartment lighting (E13/3)
- Control unit box fan motor (M4/8) (with engine 275.9)
- Windshield washer fluid pump (M5/1)
- HCS [SRA] pump (M5/2) (with code (600) Headlamp cleaning system)
- Master wiper motor (M6/6)
- Slave wiper motor (M6/7)
- Coolant circulation pump (M13)
- Steering column in/out motor
- Steering column up/down motor
- Electric air pump (M33) (with engine 156, 272, 273, 275)
- Washer nozzle heating (R2/1)
- Wiper park position heater (R2/10)
- Washer nozzle hose heater (R2/11) (with code (875) heated windshield washer system)
- Front cigar lighter with ashtray illumination (R3)
- Electric parking brake switch (S76/15)
- AC water valve (Y19/2)

Voltage supply to components
Limit switches supply power to various components and control units to match the function sequence.
Requests are notified to the front SAM control unit over either the interior CAN or directly scanned switches, transmitters an sensors. Fuses are used to protect the components and control units that have voltage applied to them against overloading. Detailed information is available in the fuse and relay box, as-built configuration specification.

Switching consumers using relays
The front SAM control unit acts as a support for the following relays over which various consumers are actuated:
- Air pump relay (N10/1kA)
- Air suspension compressor relay (N10/1kB)
- Terminal 87 relay, engine (N10/1kC)
- Terminal 15 relay (N10/1kD)
- Terminal 87 relay, chassis (N10/1kE)
- Fanfare horn relay (N10/1kF)
- Terminal 15R relay (N10/1kG)
- Circuit 50 relay, starter (N10/1kH)
- Circuit 15 relay, starter (N10/1kJ)
- Wiper park heater relay (N10/1kK)